1.The N(5)-(L-1-Carboxyethyl)-L-ornithine:NADP oxidoreductase gene has been cloned in the lambdaZAPII vector. This enzyme, (also called N(5)carboxyethylornithine synthase, EC 1.5.1.24), which mediates the biosynthesis of a family of previously unknown amino acids, has been expressed in Escherichia coli. 2.The gene for N(5)-carboxyethylornithine synthase has been sequenced, and the amino acid sequence of the enzyme has been determined. 3.It has been found that the N(5)-carboxyethylornithine synthase gene, and the genes encoding nisin synthesis and sucrose metabolism are linked and localized to a chromosomal transposon. 4.Polyclonal antibodies prepared against the purified enzyme have been used to survey for the distribution and constitutivity of the enzyme in lactic acid bacteria. 5.The mechanism(s) involved in the transport and dissimilation of fructose by the oral pathogen, Fusobacterium nucleatum have been elucidated. Mutants deficient in sugar transport systems have been isolated by UV mutagenesis, and the biochemical lesions have been identified by radiotracer techniques.